Evaluation of two new types of fillers for restorative composite resins is being conducted. One type of filler is a porous silica glass intended for anterior restorations where improved polishability is desired. The other is a porous surface nickel powder. This powder is intended to improve thewear resistance of posterior composite systems. Four experimental fully loded silane treated porous composites have been prepared from two different BIS-GMA monomer formulations and two different pore size glasses. BIS-GMA monomers were prepared to give a wide viscosity range. One porous glass filler had an average pore diameter of 2000A and the other had an average of 40A. The large pore filler was added as a single particle size and the maximum loading achieved was 41% by weight. The fine pore powder was added in a continuous size distribution and had a maximum loading of 54%. Solvent extraction techniques were used to determine the amount of residual monomer contained in the cure samples. The large pore filler lost an average of 1% and the fine pore material lost an average of .8% by weight. Large pore samples had a one day compressive strength of 21000psi and the fine pore systems have an average of 25000psi. The large pore samples had a coefficient of thermal expansion of 58 ppm and the fine pore system had a coefficient of 45 ppm.